In laying out a new "radical" drag / pulling quad, I'm open to position anything how I'd like to... to start with, I'll be using a 488 Yami 2 cycle sled motor ( only because I already have it ), but intend to run a Kawi H-2 - 750 cc 2 cycle triple, later...

why, aside from rotational reasons do they mount the motors with the exhaust ports to the front, & the carbs to the rears ??? It makes sense to me to spin the motor the other way... inertia is going to want to help feed gas into the cylinders, & help force exhaust out of the exhaust ports, if the motor was spun around... also all that heat would be behind the motor, & the carbs would be in the cooler air ??? why not ???

just to clairify... I'm not talking about the V Twins, but on side by side engines, even most single cylinder engines are layed out this way... they all seem to have the carbs behind ( in the heat ), & the exhaust ports in the front, bleeding that heat to the cylinders ???

 

Thats to keep the intake from being polluted by all of the crap you are riding into. The force of the air from the front would almost inject water, dirt and dust into your engine regardless of what filter you used.

 

that doesn't explain all the snowmobiles with fully enclosed engine compartments, or all the 70's road bikes... even on an ATV, with a normal filter box & snorkle set up, you could certainly filter the air ???

 

There isnt room in the front of most atvs for both a radiator and airbox, especially sport atvs. On a snowmobile the engine would have to be far enough forward to get the pipe bends around the engine and out the side, and you still wouldnt have room for the massive expansion chambers unless they wrapped back in front of the engine again creating the same airbox room problems. Not much room on a road bike for a forward mounted airbox and radiator either, and with an enclosed airbox you lose most of the benefit of having a forward intake, except for the cooler temperature of the air. If you had to stick the airbox behind the radiator, you wouldnt have that either.